Pogba, 23, has not scored or claimed an assist in four games since his return to United from Juventus last month.

Mourinho still trusts Pogba and says it is unfair to keep talking about his fee as, relative to United’s wealth, there were bigger transfers this summer.

The Portuguese said: “The world-record player is always a question but I want Paul to forget that.”

As a percentage of turnover, Pogba cost much less than United’s signings of Denis Law and Bryan Robson from Torino and West Brom in 1962 and 1981 respectively.

Relative to their latest turnover figure of £102.4m, Crystal Palace’s £27m purchase of Christian Benteke last month cost more than United spent to sign Pogba, given this week they confirmed annual revenue of £513m.

But after successive defeats to Manchester City and Feyenoord, the fee for Pogba is nevertheless attracting attention.

Former United midfielder Paul Scholes feels Pogba would benefit from a player in the mould of Toni Kroos or Luka Modric alongside him.

Of the present squad, Scholes believes 34-year-old Michael Carrick – who has not played since the Community Shield on 7 August – is the best fit.

However, Mourinho is not concerned at the France midfielder’s performances.

“He played in the Euro final, went on holiday, then had no pre-season,” said Mourinho. “It is normal after the first game he has a little decrease.

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Jose Mourinho defends Man Utd line-up after Feyenoord defeat

“But I am full of trust because I know he is a good guy with a lot of ambition so the form will come naturally.”

Meanwhile, Pogba’s team-mate Ander Herrera has backed Mourinho to get United back to winning ways.

Defeat at Watford on Sunday would mark club’s worst run since last December but Herrera said: “Mourinho is perfect for this club. His way of thinking is what this club wants.

“Players like Pogba and Zlatan Ibrahimovic came partly because this is a massive club but also because Mourinho is here.

“He is the right person. If you are an honest player, he is going to be an honest manager with you.”

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